1. FIELD OF THE INVENTION
This invention relates to a valve designed to be serially connected within a pipeline or the like for conveying flammable liquids and/or gasses or conveying toxic liquids and/or gasses, wherein the pipeline may be subject to fracturing due to excessive vibration or relative shifting of longitudinally spaced portions of the line (as might occur during an earthquake) or wherein the line may be exposed to extreme heat. The safety valve is operative to block the flow of liquids or gasses therethrough responsive to experiencing vibrations above a predetermined magnitude or temperatures above a predetermined temperature. However, the valve includes a reset mechanism whereby, in the event the valve is closed as a result of experiencing earthquake vibrations and the pipeline is subsequently determined to be fully operational, the valve may be manually opened.
2. DESCRIPTION OF RELATED ART
Various different forms of safety valves including some of the general structural and operational features of the instant invention heretofore have been known. Examples of safety valves presently known and believed to be even somewhat pertinent to the instant invention are disclosed in U.S. Pat. Nos. 1,022,119, 2,054,563, 2,158,753, 2,615,461, 2,713,870, 2,884,938, 4,488,566 and 4,549,717. However, these previously known forms of safety valves do not include the overall combination of structural and operational features of the instant invention.